add_executable(5_3 5_3.cc)
add_executable(5_5 5_5.cc)
add_executable(5_6 5_6.cc)
add_executable(5_19 5_19.cc)
add_executable(5_20 5_20.cc)
add_executable(5_21 5_21.cc)
add_executable(5_23 5_23.cc)
add_executable(5_24 5_24.cc)
add_executable(5_25 5_25.cc)